Secondary palate development
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The development of the secondary palate commences in the sixth week of human embryonic development. It is characterised by the formation of two palatal shelves on the maxillary prominences, the elevation of these shelves to a horizontal position, and then a process of palatal fusion between the horizontal shelves. The shelves will also fuse anteriorly upon the primary palate, with the incisive foramen being the landmark between the primary palate and secondary palate. This forms what is known as the roof of the mouth, or the hard palate.
Secondary palate development | |
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![]() Under surface of the head of a human embryo about twenty-nine days old (After His.). The palatal shelves are yet to form from the maxillary processes | |
![]() Frontal section of nasal cavities of a human embryo 28 mm. long (Kollmann) at about forty-four days. The two palatine processes can be seen here post-elevation in a horizontal position. The medial edges of the palatine processes are yet to fuse and form the roof of the oral cavity. | |
Details | |
Carnegie stage | 17 |
Precursor | Maxillary prominence |
Gives rise to | Palate, Oral cavity proper |
Anatomical terminology |
The formation and development of the secondary palate occurs through signalling molecules SHH, BMP-2, FGF-8, among others.
Failure of the secondary palate to develop correctly may result in a cleft palate disorder.